The present invention relates to an assembly for conducting and tempering fluids, as well as to a method for producing said assembly.
Certain types of fluid or gaseous media must be tempered while being conduced through hoses because these fluid or gaseous media are free-flowing or chemically resistant only within a specific temperature range.
An example of this type of fluid is a carbamide-water solution in accordance with DIN 70070 and CEFIC (European Chemical Industry Council) Regulations, which is added to the combustion gases of diesel engines, primarily to lower the emission of nitrogen oxide in order to meet the higher standards for exhaust emissions. When conducting the carbamide-water solution from a tank to the location where it is injected into the combustion gases of the diesel engine through a hose, it is necessary to equip the hose with means of tempering the solution, because, due to its chemical composition, the carbamide-water solution tends to coagulate or freeze at minus 11° C. The carbamide-water solution includes other negative characteristics such as corrosion and, depending on the temperature, creep.
Conventional hoses containing a heat conductor that is arranged inside the hose wall or fitted spirally around the circumference of the hose in longitudinal direction are known in the related art and are commercially available. In these conventional hoses, however, some of the energy generated for heating is released unused into the environment. Accordingly, in order to reduce the amount of energy required for heating the hose, recent developments in the field have shown a tendency towards using hoses having an internal heating mechanisms.
The difficulty with using a hose having an internal heating is that when connecting the hose to a connector, there is often leakage losses at the connecting region between the hose and the connector. Further, when connecting the hose to a connector, it is also difficult to separate the internal heating from the hose lumen in order to allow easy flow of the fluid in the connecting region.